The collection campaign of 2012 has nearly drawn to a close. The list of species below describes the samples collected this year. We will be adding Cupressus nootkatensis from the British Columbia Forest Service and Thuja plicata from Yellowpoint Propagation when the final processing of their seeds is complete and they are able to send us the discards.

The third x-ray round yeilded no new findings of infested seeds, but it did reveal three more potential larvae in the infested sample of Juniperus virginiana from New York Botanical Gardens when we x-rayed the remaining cones from the original sample.

This week marks the end of my contract with the project, so any questions should be forwarded to Jean-Noel.Candau@nrcan.gc.ca, otherwise you might just be waiting an awful long time for a reply! This project has taught me that there is always more going on than we think. I never even knew about the Megastigmus ‘world’ until summer 2011 and now I am the woman who buys decorative pinecones, cannot resist the urge to examine them for signs of chalcid parasitisation, and enthusiasticly proclaims to the world that she found exit holes in some of the seeds still remaining in the cones. I would have missed that joy had I not stopped to look. Take time to slow down and look for the holes in the lives of those around you that maybe, just maybe, you can help to fill.

Juniperus squamata – University of Guelph Arboretum, Arnold Arboretum of Harvard University

Juniperus virginiana – Longwood Gardens, North Carolina Botanical Gardens, University of California at Davis Arboretum, New York Botanical Gardens, Wilbur D. May Arboretum, University of Guelph Arboretum, University of Wisconsin-Madison Arboretum, Arnold Arboretum of Harvard University

After x-ray round 2 we have found larvae in six seed samples, which is exciting for the project:

Chamaecyparis thyoides from LongwoodGardens in Kennett Square, PA were infested with larvae. One sample had 5 infested seeds of a total of 175 (2.9% infestation rate) and another had 1 of 161 seeds infested (0.6%).

1 of 173 seeds were infested (0.6%) in a sample of Chamaecyparis thyoides from North Carolina Botanical Gardens. We processed two infested Chamaecyparis thyoides samples from this location last year. This result was expected both because of the findings from 2011, but also because Megastigmus thyoides was first discovered by Turgeon in North Carolina in 1994.

Two samples of Cyrptomeria japonica from New York Botanical Gardens were infested, 10 of 980 seeds (1.0%) for one sample and 181 of 1185 (15.3%) for the other. We received an infested sample of this species last year, but from another location.

Finally, 2 of 16 seeds (12.5%) from Juniperus virginiana from New York Botanical Gardens are believed to have larvae in them, but we are less sure of this result.

We have placed the infested seeds, along with any cones and seeds not used in processing the sample for x-rays, outside in our insectarium in hopes of rearing insects. In the case of Juniperus virginiana, the extra cones have been processed and we will x-ray these additionally to try and confirm larval presence.

There are 16 samples that are now prepared for the final x-ray round, as well as seed discards from 2 seedlots. We hope to acquire the discards of 4 more seedlots in the coming weeks and x-ray those as well.

Infestation of Cryptomeria japonica ‘Sekkan-sugi’ from New York Botanical Gardens

Infestation of Chamaecyparis thyoides from Longwood Gardens (one larvae inside a seed in the centre sample, 5 in the bottom left sample)

We have recieved almost all of the seed shipments for the 2012 collection campaign. We will still be recieving cones from Quarryhill Botanical Gardens and Fort Worth Botanical Garden, as well as additional seed discards from the British Columbia Forest Service and from Yellowpoint Propogation, but the majority of our seeds are either processed or ready for x-raying tomorrow. The following species have been sampled from the indicated locations across North America:

Callitropsis nootkatensis – New York Botanical Gardens

Calocedrus decurrens – University of California at Davis Arboretum

Chamaecyparis lawsoniana – Dorena Genetic Resource Center

Chamaecyparis nootkatensis – University of Guelph Arboretum

Chamaecyparis obtusa – New York Botanical Gardens, Arnold Arboretum of Harvard University

Chamaecyparis pisifera – New York Botanical Gardens, University of Guelph Arboretum, Arnold Arboretum of Harvard University

Juniperus squamata – University of Guelph Arboretum, Arnold Arboretum of Harvard University

Juniperus virginiana – Longwood Gardens, North Carolina Botanical Gardens, University of California at Davis Arboretum, New York Botanical Gardens, Wilbur D. May Arboretum, University of Guelph Arboretum, University of Wisconsin-Madison Arboretum, Arnold Arboretum of Harvard University

During the 2011 collection campaign, we collected several live insects from samples and also removed the larvae from the infested seeds once no insects had emerged from them by July 2012. We have sent these samples away to be identified. The larvae have been sent to a colleague in France for, Dr. Marie-Anne Auger-Rozenberg, who will compare the larvae phylogenetically to databases that she has complied for species of Megastigmus to see if there are any similarities or matches. Identifying insects using only larvae morphology is nearly impossible for this project, especially because processing causes the larvae to become very dry.

The insects, all from samples taken in British Columbia, have been sent to the National Identificiation Service (Entomology) at the Canadian National Collection of Insects, Arachnids and Nematodes, from which we have heard that the specimen are not Megastigmus. One sample, found on Thuja plicata from the Saanich Forestry Centre, has been identified as belonging to the Torymus sp. (Torymidae) bedeguaris species group. Torymus is a very large genus and, as such, the CNC does nothave authoritatively identified specimens in the collection for comparison to make confident identifications for most species. They have arranged for the specimen to be sent to a torymid expert in Europe, who would be more likely to be able to provide a reliable identification, particularly if it is an introduced species. The other two species of insect samples emerged from Juniperus communis/horizontalis collected at Shorts Creek Canyon by Ward Strong of the Kalamalka Forest Research Centre. They were broadly identified as Eurytoma (Eurytomidae) and Tetrastichinae (Eulophidae). In an effort to identify the species, some of the Eurytoma were taken to Washington to a Eurytomid specialist. They have now been more specifically identified as Eurytoma sp. near juniperana (Eurytomidae) and Aprostocetus sp. 1 (Eulophidae).

It is unlikely that Megastigmus is responsible for any Cupressaceae species being on the threatened or endangered species in North America. The causes are more likely loss of habitat, introduction of other alien pests or diseases, or climate change. However, when a species becomes threatened or endangered, native seed insect species or the potential introduction of an alien seed insect can become a critical factor in the survival of the species. For this reason, we have researched the Protective Status of the Cupressaceae in North America.

In Canada, no Cupressaceae are listed on the Species at Risk Public, however, according to Wild Species (http://www.wildspecies.ca) there are several species that have a less drastic status:

Juniperus maritime is listed as having a Sensitive status both at the federal level and in British Columbia

Juniperus horizontalis is listed as Sensitive in Nunavut and May Be At Risk in PEI

Thuja occidentalis is At Risk in Nova Scotia and Sensitive in PEI

Juniperus virginiana is listed as May Be At Risk in Quebec

Juniperus scopulorum is listed as May Be At Risk in Saskatchewan

Thuja plicata is listed as May Be At Risk in Alberta

There are 16 species of Cupressaceae in the United States that have protected status. From the federal government, Cupressus abramsiana has endangered status and Cupressus govenianassp. goveniana has received a threatened status. The following species have received some level of protected status from at least one state:

Since we received around half of the cone samples that we anticipate for this fall, we have x-rayed the first round of our seeds; all 18638 of them! From these samples, we have collected many midge larvae and some insects of interest, which we will identify if further examination directs us to pursue identification. In total, 28 of the 113 trees sampled displayed evidence of some form of parasitisation, either infestation of the cone, insects found with the cones, or possible exit holes on the cones or seeds. However, none of the x-rays showed that any of the seeds were infested with larvae or nymphs. Megastigmus emerge in the spring, so their larvae would be visible now and triggers for emergence are not present in fall. This means that there is likely not an infestation of Megastigmus in any of the seeds we processed. It is always a challenge to determine how we should feel at this realization, because an invasion would be unfortunate, but a novel scientific discover is always exciting!